Purpose of study: This study aimed to evaluate masticatory muscle function by using electromyography and compare the final outcome of treatment of ADDWR by using centric and anterior repositioning splint.
Patient and methods: this study was conducted on 20 patients with mean age of 29.5±3.4 complaining of anterior disc displacement with reduction of TMJ. Patients were randomly divided into two groups: I- centric splints, II- anterior repositioning splints. All patients were assessed by evaluating TMJ pain and muscle palpation, interincisal distance, joint sounds and visual analogue scale (VAS). This clinical examination was done before treatment and at 15, 30, 90, and 180 days after treatment. Also, electromyography evaluation of masseter and temporalis muscles was performed preoperative and at 3 and 6 months after treatment.
Result: In both groups, joint pain, joint click, muscle pain and interincisal distance were improved significantly. Also, significant improvement in mean amplitude and duration of masseter and temporalis muscles was achieved. There was no significant statistical difference between both groups.
Conclusion: The treatment of anterior disc displacement with reduction of TMJ with either of the two types of splint was acceptably successful and a significant reduction in the leading symptoms could be achieved. The use of occlusal splint is efficient to improve the electrical activity of the masseter and temporalis muscles.